MERCEDES SLK (2003)
Running costs, common problems, and reliability data based on 3,327 real MOT tests in 2024.
MOT Pass Rate
78%
Total Tests (2024)
3,327
Avg Mileage
85,438 mi
Est. Annual Cost
£2,397
Is the 2003 MERCEDES SLK reliable?
Average reliability. Expect some repairs as it ages. That's close to the national average of 82%. It falls below the MERCEDES brand average of 87%.
At 21 years old, 78% of MERCEDES SLKs from 2003 passed their MOT first time in 2024. That's based on 3,327 tests across the UK. The average mileage at this age is 85,438 miles.
How does the 2003 MERCEDES SLK compare?
Mileage Analysis
The average 2003 MERCEDES SLK has 85,438 miles on the clock, which is below the expected 155,400 miles for a 21-year-old car. This suggests lighter use than average, which generally means less wear on major components.
Best year to buy a MERCEDES SLK?
The most reliable year is the 2016 model with a 89% MOT pass rate, while the 1996 model has the lowest at 76%. The 2003 sits between the two at 78%.
How much does a 2003 MERCEDES SLK cost to run?
Based on 7,400 miles/year (UK average), current fuel prices, and repair likelihood from MOT pass rate data. Insurance not included.
MERCEDES SLK by Year
| Year | Pass Rate | Tests | Avg Mileage |
|---|---|---|---|
| 2016 | 89% | 2,572 | 42,977 mi |
| 2015 | 87% | 11,055 | 48,710 mi |
| 2014 | 87% | 11,284 | 55,581 mi |
| 2013 | 85% | 11,106 | 62,322 mi |
| 2012 | 84% | 13,361 | 64,940 mi |
| 2011 | 85% | 5,660 | 61,469 mi |
| 2010 | 80% | 4,472 | 66,541 mi |
| 2009 | 81% | 5,347 | 71,532 mi |
| 2008 | 80% | 6,876 | 75,187 mi |
| 2007 | 79% | 7,700 | 77,695 mi |
| 2006 | 79% | 7,884 | 80,213 mi |
| 2005 | 78% | 10,305 | 82,791 mi |
| 2004 | 78% | 6,598 | 84,132 mi |
| 2003 | 78% | 3,327 | 85,438 mi |
| 2002 | 81% | 3,692 | 87,295 mi |
| 2001 | 82% | 4,005 | 90,848 mi |
| 2000 | 79% | 3,545 | 90,918 mi |
| 1999 | 79% | 4,295 | 87,626 mi |
| 1998 | 79% | 3,523 | 89,671 mi |
| 1997 | 81% | 2,190 | 90,802 mi |
| 1996 | 76% | 126 | 98,709 mi |
Checking a specific MERCEDES SLK?
Enter the reg plate to see its individual MOT history, mileage verification, and predicted costs.
About the 2003 MERCEDES SLK
The 2003 MERCEDES SLK is a large car with a 2295cc petrol engine. 3,327 of these vehicles were MOT tested in 2024, making it a reasonably common sight on UK roads. Among all cars from 2003, the average MOT pass rate is 72%, and this model beats that benchmark.
With an average of 85,438 miles at 21 years old, MERCEDES SLK owners tend to use this car less than the typical driver.
2003 MERCEDES SLK Fuel Costs
The 2295cc petrol engine offers a reasonable balance between performance and economy. Expect around 30 mpg in mixed driving, which works out to roughly £1,592 per year at current petrol prices of 142p per litre (based on 7,400 miles per year).
What does it cost to own a 2003 MERCEDES SLK?
Total estimated annual running cost is £2,397 (£200/month), broken down as £1592 fuel, £250 road tax, £55 MOT, and £500 predicted repairs. Repair costs are moderate, reflecting the 78% pass rate. Keeping on top of servicing will help avoid surprises.
MERCEDES SLK Reliability Trend
Newer MERCEDES SLKs show better MOT pass rates than older ones, with an average improvement of 4 percentage points.
Buying a Used 2003 MERCEDES SLK
At 21 years old, the MERCEDES SLK is firmly in budget territory. Purchase prices are low, but check for rust, worn suspension bushes, and electrical gremlins. A full service history is especially valuable at this age. If you're flexible on year, the 2016 model has the highest pass rate at 89%.
Alternatives to the 2003 MERCEDES SLK
The MERCEDES SLK is actually the most reliable option among similar petrol large cars from this era. Here are comparable petrol cars with similar engines:
- RENAULT CLIO (2005) 67% pass rate (-11%) from 18,423 tests
- MERCEDES C (2005) 73% pass rate (-5%) from 17,978 tests
- HONDA CR-V (2005) 70% pass rate (-8%) from 16,222 tests
- LAND ROVER FREELANDER (2005) 69% pass rate (-9%) from 11,705 tests